am42dl3224gt71it Meet Spansion Inc., am42dl3224gt71it Datasheet - Page 20

• Manufacturer Part Number: am42dl3224gt71it
• Description: Stacked Multi-chip Package Mcp Flash Memory And Sram 32 Megabit 4 M X 8-bit/2 M X 16-bit Cmos 3.0 Volt-only, Simultaneous Operation Flash Memory And 4 Mbit 256 K X 16-bit Static Ram
• Manufacturer: Meet Spansion Inc.

The hardware sector protection feature disables both
program and erase operations in any sector. The hard-
ware sector unprotection feature re-enables both
program and erase operations in previously protected
sectors. Note that the sector unprotect algorithm un-
protects all sectors in parallel. All previously protected
sectors must be individually re-protected. To change
data in protected sectors efficiently, the temporary
sector un protect function is available. See “Temporary
Sector/Sector Block Unprotect”.
Sector protection and unprotection can be imple-
mented as follows.
Sector protection and unprotection requires V
RESET# pin only, and can be implemented either
in-system or via programming equipment. Figure 1
20
SA22–SA19
SA69-SA67
SA66-SA63
SA62-SA59
SA58-SA55
SA54-SA51
SA50-SA47
SA46-SA43
SA42-SA39
SA38-SA35
SA34-SA31
SA30-SA27
SA26-SA23
SA18-SA15
SA14-SA11
Table 9. Bottom Boot Sector/Sector Block
SA10-SA8
Sector
SA70
Addresses for Protection/Unprotection
SA7
SA6
SA5
SA4
SA3
SA2
SA1
SA0
1010XXXXX
1001XXXXX
1000XXXXX
0101XXXXX
0100XXXXX
0010XXXXX
0001XXXXX
000011XXX,
000010XXX,
111101XXX,
1110XXXXX
1101XXXXX
1100XXXXX
1011XXXXX
0111XXXXX
0110XXXXX
0011XXXXX
111110XXX,
000001XXX
111100XXX
111111XXX
000000101
000000100
000000010
000000001
000000000
000000111
000000110
000000011
A20–A12
Sector/Sector Block
192 (3x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
192 (3x64) Kbytes
64 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
Size
P R E L I M I N A R Y
ID
on the
Am42DL32x4G
shows the algorithms and Figure 26 shows the timing
diagram. This method uses standard microprocessor
bus cycle timing. For sector unprotect, all unprotected
sectors must first be protected prior to the first sector
unprotect write cycle.
The device is shipped with all sectors unprotected.
It is possible to determine whether a sector is pro-
tected or unprotected. See the Autoselect Mode
section for details.
Write Protect (WP#)
The Write Protect function provides a hardware
method of protecting certain boot sectors without
using V
WP#/ACC pin.
If the system asserts V
vice disables program and erase functions in the two
“outermost” 8 Kbyte boot sectors independently of
whether those sectors were protected or unprotected
using the method described in “Sector/Sector Block
Protection and Unprotection”. The two outermost 8
Kbyte boot sectors are the two sectors containing the
lowest addresses in a top-boot-configured device, or
the two sectors containing the highest addresses in a
top-boot-configured device.
If the system asserts V
vice reverts to whether the two outermost 8 Kbyte boot
sectors were last set to be protected or unprotected.
That is, sector protection or unprotection for these two
sectors depends on whether they were last protected
or unprotected using the method described in “Sec-
tor/Sector Block Protection and Unprotection”.
Note that the WP#/ACC pin must not be left floating or
unconnected; inconsistent behavior of the device may
result.
Temporary Sector/Sector Block Unprotect
(Note: For the following discussion, the term “sector”
applies to both sectors and sector blocks. A sector
block consists of two or more adjacent sectors that are
protected or unprotected at the same time (see Table
8).
This feature allows temporary unprotection of previ-
ously protected sectors to change data in-system. The
Sector Unprotect mode is activated by setting the RE-
SET# pin to V
formerly protected sectors can be programmed or
erased by selecting the sector addresses. Once V
removed from the RESET# pin, all the previously pro-
tected sectors are protected again. Figure 1 shows the
algorithm, and Figure 25 shows the timing diagrams,
for this feature.
ID
. This function is one of two provided by the
ID
(11.5 V – 12.5 V). During this mode,
IL
IH
on the WP#/ACC pin, the de-
on the WP#/ACC pin, the de-
May 19, 2003
ID
is